Contraception Flashcards
What are the different groups of contraceptives?
- Combined Hormonal Contraception (CHC)
- pills, patch, vaginal ring
- Progestogen only methods
- pill, injectable, implant, IUD
- copper Intrauterine Device (IUD)
- emergency contraception
- sterilisation
- barrier method
- condoms, diaphragm
What is The Pearl Index?
The number of contraceptive failures per 100 women-years of exposure.
It looks at total months/cycles of exposure from the initiation of the product to the end of the study.
What is Life Table Analysis?
The contraceptive failure rate over a specified time frame and cumulitive failure rate for any specific length of exposure.
What is meant by;
method failure + user failure?
- method failure- pregnancy depite correct use of method by user
- user failure- pregnancy because method is not used correctly by user
* Long Acting Reversible Contraception (LARC) minimises user input ∴ minimises user failure rates
At what point in the uterine cycle is pregnancy most likely?
- ovulation 12-18 (2 weeks before period)
- egg survives 24hrs + sperm < 4 days
∴ highest chance of pregnancy day 8-19
What hormones are in Combined Hormonal Contraception, what do they do
and how is each method used?
- ethinyl estradiol (EE)
- sythetic progesterone (progestogen)
- stop ovulation, thicken cervical mucous, thin endometrium
- 21 days with hormone free week/tricycling/continuous
- pill- taken daily
- not good if frequent GI upset
- patch (EVRA)- changed weekly
- < 5% have skin reaction
- ring (Nuvaring)- changed every 3 weeks
- can be taken out 3/24hrs
- latex free
What are some non-contraceptive benefits of Combined Hormonal Contraception?
- regulate/reduce bleeding
- stop ovulation (help PMS)
- dec. funtional ovarian cysts
- 50% dec. ovarian + endometrial cancer
- dec. benign breast disease, rheumatoid arthritis, colon cancer, osteoporosis
- improve acne/hirtuism
What are some side effects of Combined Hormonal Contraception?
- breast tenderness
- nausea
- headache
- irregular bleeding (first 3 months)
- effect mood
- weight gain
What are some serious risks of using Combined Hormonal Contraception?
- venous thrombosis (DVT, PE)
- contraindications; BMI > 34, previous VTE, 1st ° relative < 45 VTE, thrombophilia
- arterial thrombosis (MI, ischaemic stroke)
- contraindications; smokers > 35, previous ATE, focal migraine, age > 50, BP > 140/90
- inc. risk cervical cancer
- inc. risk breast cancer
* avoid if active gallbladder disease or previous liver tumour
What does the Progestogen Only Pill (POP/minipill) do and how is it used?
- Desogestrel (12hr window)
- stops ovulation, thickens mucous
- most bleed free
- LGN NET (3hr window)
- 1/3 stops ovulation, thickens mucous
- 1/3 bleed free, 1/3 regular, 1/3 irregular
- pill taken same time every day
- not good if frequent GI upset
What are progestogenic side effects and risks?
- inc. appetite
- hair loss/gain
- mood change
- bloating/retention
- headache
- acne
* avoid if current breast cancer or past/present liver tumour
How is injectable progestogen (the jag) administered and what does it do?
- Depoprovera (depomedroxyprogesterone acetate)
- 150mg 1ml, deep IM injection, upper outer quadrant of buttock, every 13 weeks
- Sayana press
- 0.6ml SC injection, self administered
- prevents ovulation
- thickens mucous
- thins endometrium
What are side effects of injectable progestogen?
- 70% amenorrhoeic affter 3 doses
- irregular bleeding (esp. first 2 doses)
- delay in return to fertility (average 9 months)
- reversible reduction in bone density
- 2/3 women gain 2-3kg
What is the subdermal progestogen implant (the rod) made of and what does it do?
- Nexplanon- etonegestrel ENG (core) + ethinyl vinyl acetate EVA (membrane)
- prevents ovulation
- thickens mucous
* lasts up to 3 years
What are side effects of the subdermal progestogen implant?
- 60% bleed free
- 30% prolonged/frequent bleeding
- most likely to cause mood change, compared to other progestogen only methods
What does the copper Intrauterine Device (IUD) do and what are its side effects?
- toxic to sperm- prevent sperm reaching egg
- can prevent implantation of fertilised egg
- can make periods heavier/crampier
* hormone free
* can last 5-10 yrs (depends on type)
What does the Levonorgestrel Intrauterine System do,
what hormone does it use,
what are its side effects,
what are the different types?
- thickens mucous
- thins endometrium
- can prevent implantation of fertilised egg
- progestogen (relatively low level)
- reduced bleeding, after 4 months irregular bleeding
- Mirena- 5 years
- also treatment for heavy bleeding + HRT
- Kyleena- 5 years *
- Jaydess- 3 years *
* less hormones but still as effective,
less likely to be bleed free, less side effects
What are different methods of emergency contraception,
up to when are they effective,
what is the rate of failure?
- copper IUD (most effective)
- within 120 hrs OR by day 19 of cycle
- < 1%
- Ulipristal pill (Ellaone) *
- within 120 hrs
- 1-2%
- Levonorgestrel pill (Levonelle)
- within 72 hrs
- 2-3%
* Ellaone- contraindications; breast feeding, enzyme inducing drugs, acid reducing drugs
When does contraception become effective and when is pregnancy possible again after a current pregnancy?
- immediate protection, if started in first 5 days of cycle
- after 7 days, if any other time in cycle
- pregnancy possible 21 days after delivery OR 5 days after miscarriage or abortion
- breast feeding is contraceptive for 6 months if; feeding every 4 hrs + amenorrhoeic
What is the usual method of female sterilisation and what are its side effects?
- laparoscopic sterilisation- Filshie clips applied to fallopian tube block tube lumen
- can do salpingectomy at C-section if well planned and baby well
- risks of GA and laparoscopy
- irriversible
- failure 1/200 over lifetime- ectopic risk
- no effects on periods/hormones
- reduces ovarian cancer risk
What is the usual method of male sterilisation and what are its side effects?
- vasectomy- vas deferens divided and ends cauterised, small incision midline scrotum
- takes 4-5 months to be effective
- failure rate 2 %
- irreversible- sperm antibodies even if vas reconnected
- < 1% risk long term testicular pain
What fraction of women will have an abortion and what is the most common age group?
- 1/3 in the UK
- 1/6 in Grampian
- 20-24 age group
What are the 2 methods of abortion, when are they performed, what are the complications?
- Surgical (STOP)- 5-12 weeks
- Misoprostol, to dilate cervix
- GA/LA cervical block
- transcervical 6-10mm suction catheter
* 0.1-0.4% risk perforation, < 1% cervical injury
* infection
* risk from GA - Medical (MTOP)- 5-24 weeks
- Mifepristone, antiprogestogen tablet
- Misopristol (can be taken at home), dilates cervix + expels pregnancy
- average 4-6 hrs to pass < 12 weeks pregnancy
* failure 1% if < 8 weeks, 8% if > 12 weeks- need surgery for incomplete abortion
* infection
* < 0.1% need blood transfusion
